A standard shuttleless loom is provided with a pair of longitudinally moving weft inserters formed as lances or ribbons that move between the upper and lower shed-defining parts of the warp to pass the weft filament therethrough. These inserters are supported longitudinally, which direction is parallel to the weft and perpendicular to the warp, and laterally. Each such inserter has an inner end provided with a gripper and the two inserters are oppositely but synchronously reciprocated so that the weft yarn held in the gripper of one of the inserters and pulled thereby along the shed to the center of the warp can be released by this one inserter and taken up by the gripper of the other inserter which in turn will pull it the rest of the way through the shed formed in the warp.
As described in U.S. Pat. No. 4,515,185 the grippers are synchronously opened and closed in an exchange zone in the middle of the warp by a lever mechanism that engages the head of each of the inserters where the respective grippers are mounted. The inserters themselves are supported on guide blocks or plates distributed along the width of the fabric being woven. The known system has the main disadvantage that in the middle exchange zone where a support plate receives the opening effort of the gripper exerted by the operating lever, the lower warp filaments are pinched which risks damaging them. It is also possible to verify with this known system that certain parts wear excessively, in particular the inserters where they contact the support and guide elements.